1. Field of the Invention
The present invention relates to flame-retarding and, in particular, to compositions, products and methods that utilize superabsorbent polymers for flame-retarding.
2. Description of the Related Art
Superabsorbent materials generally are known as materials which can absorb up to about one thousand (1000) times their weight in distilled water. Superabsorbent materials, such as superabsorbent polymers (SAPs), for instance, are utilized in numerous applications. SAPs are commonly used in incontinent products, such as diapers, and other hygiene products, primarily due to their aforementioned water-absorption characteristics. SAPs also possess certain water-blocking characteristics which are utilized in numerous other applications, such as by incorporating the SAPs into telecommunications and power cables, as described in U.S. Pat. No. 4,867,526, issued to Arroyo, for example. In these applications, the SAPs typically are incorporated below the outer jacket of the cable, such as in a water-blocking tape, for instance. Upon contact with water, the SAPs absorb the water and swell, thereby preventing migration of the water through the cable. Additionally, the swelled SAPs form a physical barrier which prevents more water from entering the cable.
In many applications, a combination of water-blocking and flame-retarding is desired. Heretofore, a prior art solution to attain the characteristics of water-blocking and flame-retarding has been to add flame-retardants to SAPs. However, this oftentimes results in a SAP composition which has reduced water-blocking characteristics as compared to the SAPs without the flame-retardants. Primarily, this is due to the chemical properties of the prior art flame-retardants which, typically, are salts or ionic compounds that are known to reduce the swelling of water-blocking materials. Generally, as more prior art flame-retardants are added to SAPs in an effort to improve their flame-retarding characteristics, the greater the water-blocking capacity of the SAPs is reduced. Frequently, the extent of reduction in water-blocking capacity of SAPs due to incorporation of flame-retardants can render the SAPs incapable of preventing water penetration.
Therefore, there is a need for improved compositions, products and methods which address these and other shortcomings of the prior art.